Collapsible concrete-form.



E. G. WATSON.

GOLLAPSIBLE CONCRETE FORM.

APPLICATION FILED .APBM, 1913.

Patented Mar. 9, 1915.

ELllIER G. WATSON, OF COLLEGE PLACE, WASHINGTON. I Q

COLLAPSIBLE coNcnETE-roruvi.

. Specification of Letters Patent.

Patented'Mar. 9, 1915.

Application filed April 14, 1913. Serial No. 760,869.

To all whom it may concern:

Be it known that I, ELMER G. WATSON, a citizen of the United States,residing at College Place, in the county'of lValla Walla and State ofWashington, have invented certain new and useful Improvements inCollapsible Concrete-Forms, of which the following is a specification.

My invention relates to improvements in collapsible concrete forms, thepresent embodiment being particularly designed and adapted for use inthe formation of concrete structures where an arch 'or vaultedpassageway is desired, as in bridges, culverts, drainage and sewerstructures, fiumes, and the like. a

The primary object of the invention is to provide a generally improvedcollapsible form for such concrete structures of exceedingly simple,cheap, and efficient construction, which may be readily set up for use,

and when the concrete has become sufficiently set or hardened, may bereadily collapsed and removed.

With the above mentioned and other ends in view, the invention consistsin the novel. construction, arrangement, and comblnation of parts,hereinafter described, illustrated in one of its embodiments in theaccompanying drawings, and particularly pointed out in the appendedclaims.

Referring to the drawings, forming a part of this specification, Figure1, is a perspective view of the improved form set up for use. Fig. 2, across sectional view of the same surrounded by a completed concretestructure, and illustrating its application and use. Fig. 3, aperspective view of the improved collapsible base structure orsupportdetached from the arch or flank members. Fig. 4, a top plan view of theadjacent or crown portions of the arch members and the interposedremovable key member, certain portions being broken away for the purposeof clearer illustration.

Similar numerals of reference designate like parts throughout all thefigures of the drawings.

The improved collapsible concrete form, in its present embodiment,comprises segmental arch or flank members 1, adapted to be supported intheir set up position by means of a removable key member 2, said keymember 2, being interposed between the crown portions 1*, of the archmembers and preferably slidably mounted between the-same, as here--inafter described.

The curved arch members may be forme of any suitable and convenientmaterial, and, in the present instance, comprise curved metallic straps'l yand a pluralityoof'surrounding or superposed longitudinally.extending strips bolted to the curved straps or supports 'l f i As ameans for supporting orexpanding and contracting the base portions ofthe segmental arch members 1, a contractible support is movablyconnected to the base portions of the arch members, said contractiblesupport comprising a longitudinally extending king beam or operatingmember A, provided at its sides with a plurality of laterally extendingtie beams or members 3, the latter being hingedly or pivotally connectedto the sides of the operating member A, in the present instance, bymeans of hinge members 3 As a means for connecting the outer ends of thetie beams 8, to the base portions of the segmental arch members, thelatter are provided with eye bolts 4, connected to clevis members 5, onthe outer ends of the tie members 3.

As a convenient means for removably and slidably mounting the key member2, between the crown portions 1, of the segmen: tal arch members, saidkey member is preferably provided at its sides with track or guideways6, formed, in the present instance, 1 by means of a round'bar or rodbent upon moval or'insertion of the key member. '2.

When it is desired to bring the improved concrete form into use, as forexample,-in forming a concrete culvert or tile, as illustrated in Fig.2, of the drawings, the ditch or excavation is first made, after whichthe bottom 8, of the concrete structure is first .formed and leveled OE,and the improved concrete form is then placed thereon and set up and theremaining portions of the 2, may be withdrawn longitudinally by means ofthe handle 6, and the operating beam or member A, may be drawnlongitudinally or outwardly by means of the loop handle A thereon,thereby contracting the contractible support and drawing the baseportions of the segmental arch members inwardly so that the latter becollapsed and the entire concrete form removed.

From the-foregoing description, taken in connection with the.accompanying drawings, the operation and advantages of my invention willbe readily understood.

Having thus described one-of the embodiments of my invention, what Iclaim and desire to secure by Letters Patent is,-

1. In a collapsible concrete form, the combination with segmental archmembers provided at their crown portions with guide pulleys and at theirbase portions with contractible tie supports; of a key member interposedbetween the crown portions of said i members interposed between saidguide puls leys, and a longitudinally extendingvoperatingmember providedwith a plurality of pivotally mounted tie members connected to I thebase portions of said segmental arch members.

In testimony whereof I have afliKed my signature in presence of twoWltIlGSSBS:

ELMER G. WATS Witnesses ED. DERRY, ALBERT O. 'HARBAUGH.

Copies of this patent may be obtained for five cents eaclnbyaddressingthe Commissioner of; Patents,

' Washington, I). C.

